This invention relates to electrical protective equipment and is particularly directed to protective housings for household electrical outlet receptacles which can be used either while electrical cords are connected to the outlet or the outlet is not in use. The problem addressed is the protection of incompetent persons from the injury due to accidental misuse of electrical outlet receptacles. There is need for protection of curious and crawling infants from electrical shocks, either by unprotected outlets or by playing with electrical cords or plug prongs.
The concept of protecting children and animals from outlet hazards or playing with electrical cords has long been recognized in the prior art. These devices incorporate a cover, however, these past devices are either cumbersome to install, requiring removal or replacement of the outlet cover plate by the householder, or require a tool to remove and replace the cover when an electrical cord is to be connected or disconnected from an outlet, or they do not incorporate tamper resistant cover locking features which tend to make them less "child proof". These past devices are likewise often unsightly or bulky or include protrusions which can catch clothing, draperies or the like.
MacDonald, U.S. Pat. No. 3,434,618, Grimes, U.S. Pat. No. 2,891,102 and McGann, U.S. Pat. No. 2,892,172, each show an electrical outlet guard which is held over the electrical outlet by a screw. These guards require a tool to remove and replace or provide a screw knob for children to play with.
Tait et al, U.S. Pat. No. 3,491,327 shows a cover which slides into position by wedging a flange under the existing cover plate of an electrical outlet. This requires the householder to loosen the cover plate to control pressure. The cover is easily slid off, there being no positive tamper resistant interlocking device incorporated.
Ruskin, U.S. Pat. No. 2,880,264, shows a cover which is hinged on one side to pivot into position and which requires replacement of the cover plate. A single catch bar is inserted into a slot in the cover plate.
Gregg, U.S. Pat. No. 2,526,606, shows a protective cover which requires a removal and replacement of the receptacle cover plate. This cover plate carries protruding retaining ears which can be broken off when the cover is pried.
Kilgore, U.S. Pat. No. 2,510,745, requires removal of the receptacle cover plate and utilizes a quick release button and prong latching design.
Chrones, U.S. Pat. No. 4,070,078, shows an integral new cover plate and hinged cover boxes which utilize a projecting latch element on the face of the plate.
Horne, U.S. Pat. No. Des. 261,135, shows a cover which is held over a base frame by friction pressure without any positive interlock and which normally would require a pry tool to remove.
These prior art devices show protective covers which are relatively complicated, or require a relatively large number of parts, or do not incorporate tamper resistant interlocking means. Moreover, they do not provide a structure which withstands yanking and pushing with little or no fatiguing of parts.
The objects of this invention are to provide a strong, tamper resistant yet simple protective cover which is economical to manufacture and easy to install and which does not require replacement of the original cover plate, but is easily "opened" and then "recovered " without the use of tools.